/*
 * Copyright (C) 2013 Brett Wooldridge
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.zaxxer.hikari.util;

import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Locale;
import java.util.Properties;
import java.util.Set;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.zaxxer.hikari.HikariConfig;

/**在目标对象上反射地设置bean属性的类
 * <br/>A class that reflectively sets bean properties on a target object.
 *
 * @author Brett Wooldridge
 */
public final class PropertyElf {
	private static final Logger LOGGER = LoggerFactory.getLogger(PropertyElf.class);

	private static final Pattern GETTER_PATTERN = Pattern.compile("(get|is)[A-Z].+");

	public static void setTargetFromProperties(final Object target, final Properties properties) {
		if (target == null || properties == null) {
			return;
		}

		List<Method> methods = Arrays.asList(target.getClass().getMethods());
		properties.forEach((key, value) -> {
			// 属性名称要以dataSource.开头，把属性值放入HikariConfig对象对应的属性里
			if (target instanceof HikariConfig && key.toString().startsWith("dataSource.")) {
				((HikariConfig) target).addDataSourceProperty(key.toString().substring("dataSource.".length()), value);
			} else {
				setProperty(target, key.toString(), value, methods);
			}
		});
	}

	/**
	 * Get the bean-style property names for the specified object.
	 *
	 * @param targetClass the target object
	 * @return a set of property names
	 */
	public static Set<String> getPropertyNames(final Class<?> targetClass) {
		HashSet<String> set = new HashSet<>();
		Matcher matcher = GETTER_PATTERN.matcher("");
		for (Method method : targetClass.getMethods()) {
			String name = method.getName();
			if (method.getParameterTypes().length == 0 && matcher.reset(name).matches()) {
				name = name.replaceFirst("(get|is)", "");
				try {
					if (targetClass.getMethod("set" + name, method.getReturnType()) != null) {
						name = Character.toLowerCase(name.charAt(0)) + name.substring(1);
						set.add(name);
					}
				} catch (Exception e) {
					continue;
				}
			}
		}

		return set;
	}

	public static Object getProperty(final String propName, final Object target) {
		try {
			// use the english locale to avoid the infamous turkish locale bug
			String capitalized = "get" + propName.substring(0, 1).toUpperCase(Locale.ENGLISH) + propName.substring(1);
			Method method = target.getClass().getMethod(capitalized);
			return method.invoke(target);
		} catch (Exception e) {
			try {
				String capitalized = "is" + propName.substring(0, 1).toUpperCase(Locale.ENGLISH)
						+ propName.substring(1);
				Method method = target.getClass().getMethod(capitalized);
				return method.invoke(target);
			} catch (Exception e2) {
				return null;
			}
		}
	}

	public static Properties copyProperties(final Properties props) {
		Properties copy = new Properties();
		props.forEach((key, value) -> copy.setProperty(key.toString(), value.toString()));
		return copy;
	}

	private static void setProperty(final Object target, final String propName, final Object propValue, final List<Method> methods) {
		// use the english locale to avoid the infamous turkish locale bug
		String methodName = "set" + propName.substring(0, 1).toUpperCase(Locale.ENGLISH) + propName.substring(1);
		Method writeMethod = methods.stream().filter(m -> m.getName().equals(methodName) && m.getParameterCount() == 1).findFirst().orElse(null);

		if (writeMethod == null) {
			String methodName2 = "set" + propName.toUpperCase(Locale.ENGLISH);
			writeMethod = methods.stream().filter(m -> m.getName().equals(methodName2) && m.getParameterCount() == 1).findFirst().orElse(null);
		}

		if (writeMethod == null) {
			LOGGER.error("Property {} does not exist on target {}", propName, target.getClass());
			throw new RuntimeException(String.format("Property %s does not exist on target %s", propName, target.getClass()));
		}

		try {
			Class<?> paramClass = writeMethod.getParameterTypes()[0];
			if (paramClass == int.class) {
				writeMethod.invoke(target, Integer.parseInt(propValue.toString()));
			} else if (paramClass == long.class) {
				writeMethod.invoke(target, Long.parseLong(propValue.toString()));
			} else if (paramClass == boolean.class || paramClass == Boolean.class) {
				writeMethod.invoke(target, Boolean.parseBoolean(propValue.toString()));
			} else if (paramClass == String.class) {
				writeMethod.invoke(target, propValue.toString());
			} else {
				writeMethod.invoke(target, propValue);
			}
		} catch (Exception e) {
			LOGGER.error("Failed to set property {} on target {}", propName, target.getClass(), e);
			throw new RuntimeException(e);
		}
	}
}
